1. Field of the Invention
The present invention relates to a method of diagnosing degradation of a welding system, and more particularly to a method of diagnosing electrical degradation of a welding system used in a vehicle manufacturing process.
2. Background Art
Welding systems are used to weld metal components together in vehicle assembly operations. A welding system may adjust current output to compensate for resistance variations in an electrical welding circuit. Resistance variations may be related to the workpieces being welded or the degradation of welding system equipment.
Previously, welding systems were unable to distinguish between resistance variations associated with workpieces, such as contamination or improper positioning, and resistance variations due to the equipment degradation. As a result, equipment degradation was not diagnosed until unexpected equipment failure occurred, resulting in downtime and reduced productivity.
Before Applicant's invention, there was a need for a method that accurately diagnosed degradation of a welding system. In addition, there was a need for a method that detected and signaled the deterioration of welding system components prior to failure. In addition, there was a need for a diagnostic method that was sensitive to resistance variations caused by equipment degradation. In addition, there was a need for a method that could be automated and implemented without increasing cycle time or decreasing equipment availability. In addition, there was a need for a method that could be integrated with vehicle assembly operations. Problems associated with the prior art as noted above and other problems are addressed by applicant's invention as summarized below.